1. Field of the Invention
The present invention relates to a method for determining the dimensional accuracy of workpiece surfaces. The method includes placing a measuring device with a sensor in an operational position relative to the workpiece surface in which the sensor delivers measurement data to the measuring device while changing the angular position relative to the workpiece.
The present invention further relates to an apparatus for carrying out the above-described method. The apparatus includes a holding device for the sensor and the workpiece in order to facilitate a relative sliding and rotating movement between the workpiece and the sensor along or about the axis of the workpiece surface.
2. Description of the Related Art
Particularly in the manufacture of high precision, cylindrical workpiece surfaces which are usually produced by means of powerful and, thus, relatively expensive tools, the tools being used are required to have an extremely long service life. The desired long service life can only be achieved if the quality of processing is monitored to a sufficient extent. Therefore, it has been attempted in the past to integrate in a processing center measuring devices which scan the already processed workpiece surface point by point, so that the measurement signals can be used in the manufacture. For this purpose, a measuring unit which is independent because of an integrated voltage source is equipped with a chucking cone for the coupling to a holding means of the tool system.
Compared to a quality control in which the processed workpiece must be transported to a separate measuring point either manually or by means of a manipulating device, for example, an industrial robot, the above-described method has the advantage that the positional accuracy of the processed workpiece surface in space can be monitored with relatively simple means and with high precision at the same time. It has been found particularly disadvantageous that the processed workpiece surface can only be measured point by point with the workpiece standing still because the scanners would be ground off too quickly when the workpiece rotates. In addition, particularly when a large number of chips are produced, the workpiece surface must be cleaned frequently prior to scanner contact. These and other measures have the consequence that the measuring procedure takes a long time and the workpiece cannot be measured between the measuring points. Therefore, the integration of the measuring procedure into the continuing manufacturing process was not possible in the past.